When data is stored in memory, it is important to have a mechanism that can detect and correct a certain number of errors in the stored data. Error correction code (ECC) encodes data in such a way that errors in the data can be identified and corrected when the data is decoded. For example, data strings can be encoded by an ECC encoder by adding a number of redundant and/or parity bits to create corresponding codewords. When an original data string is to be retrieved from the memory, an ECC decoder can use the corresponding codewords to identify bit errors in the encoded data string. If bit errors are present, one or more ECC operations can be employed to correct the bit errors and to recover the original data string.
In addition to outputting error-checked and/or error-corrected data, some implementations of the ECC can also generate metadata regarding an ECC decode operation. For example, ECC operations can generate a bit error count (e.g., the number of bit errors identified and/or corrected) corresponding to a decoded codeword. Because the metadata can provide an indication of the health or quality of memory regions storing each codeword, the metadata is frequently referred to as a quality metric of the memory regions.